The california scents cans are meant to be a hit!
Horney got me a California Scents for my birthday mid December and it's still going strong.. At just the right amount of pong too!
dragonfly-Try autosmart spray. One blast can last a couple days and I will last well over a year. Cali scents just dry out over a month but you are ment to 'recharge' them with some drops of water.+ cali scents are quite ugly looking things http://www.ebay.co.uk/itm/Autosmart-Car-Air-Freshener-Bubblegum-Blast-Valeting-x4-/300654847383?pt=UK_Car_Accessories_Car_Care_Cleaning&hash=item46006ce597